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Date: Tue, 25 Jan 2011 17:10:49 -0500
From: Mark Lord <kernel@teksavvy.com>
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To: "Ahmed S. Darwish" <darwish.07@gmail.com>
CC: James Bottomley <James.Bottomley@suse.de>, Tejun Heo <tj@kernel.org>,
        Ingo Molnar <mingo@elte.hu>, "H. Peter Anvin" <hpa@zytor.com>,
        Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@redhat.com>,
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Subject: Re: [PATCH 0/2][concept RFC] x86: BIOS-save kernel log to disk	upon
 panic
References: <20110125134748.GA10051@laptop> <20110125140948.GA26762@elte.hu> <20110125153649.GA11386@laptop> <1295971355.4955.104.camel@mulgrave.site> <20110125170522.GA16285@laptop>
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On 11-01-25 12:05 PM, Ahmed S. Darwish wrote:
>
> My current x86 laptop includes the very common ATA PIIX controller. 


ata_piix is just about ideal for this sort of thing.

Except, don't use the BIOS to write the logs,
but rather code/use a very simple set of polling-PIO
functions to talk directly through the PIIX to the drive.

Really really simple code to do that, and it would likely
work with anything ata-piix, and most other non-AHCI chipsets too.

Not perfect, but probably good enough for a lot of scenarios.
The old hd.c driver shows how to read/write a sector at a time,
and that kind of code is easily converted to simply poll for completion.

Cheers